fix: workaround error when 'fanstatic.needed' missing from environ

apparently the previous fix doesn't actually get us past the error;
this one should do a better job although it's still not perfect
either.  for some reason the redirect to 'home' route is confused such
that it the new URL drops the ending filename but the rest remains, so
it's not really the home URL..  oh well at least this is better than
before

src/wuttaweb/handler.py

@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  wuttaweb -- Web App for Wutta Framework
-#  Copyright © 2024 Lance Edgar
+#  Copyright © 2024-2025 Lance Edgar
 #
 #  This file is part of Wutta Framework.
 #
@@ -70,16 +70,8 @@ class WebHandler(GenericHandler):
         url = self.config.get("wuttaweb.favicon_url")
         if url:
             return url
-
-        # nb. in rare circumstances i have received unhandled error email,
-        # which somehow was triggered by 'fanstatic.needed' being missing
-        # from the environ.  not sure why that would happen, but it seems
-        # safe to ignore when it does - favicon is not *that* important.
-        if "fanstatic.needed" in request.environ:
         return self.get_fanstatic_url(request, static.favicon)
 
-        return ""
-
     def get_header_logo_url(self, request):
         """
         Returns the canonical app header image URL.

src/wuttaweb/subscribers.py

@@ -41,6 +41,7 @@ import logging
 from collections import OrderedDict
 
 from pyramid import threadlocal
+from pyramid.httpexceptions import HTTPFound
 
 from wuttaweb import helpers
 from wuttaweb.db import Session
@@ -123,6 +124,17 @@ def new_request(event):
     config = request.registry.settings["wutta_config"]
     app = config.get_app()
 
+    # nb. in rare circumstances i have received unhandled error email,
+    # which somehow was triggered by 'fanstatic.needed' being missing
+    # from the environ.  not sure why that would happen, but it seems
+    # to when crawlers request a non-existent filename under the
+    # fanstatic path.  there isn't a great way to handle it since
+    # e.g. can't show the normal error page if JS resources won't
+    # load, so we try a hail-mary redirect..
+    # (nb. also we skip this if environ is empty, i.e. for tests)
+    if request.environ and "fanstatic.needed" not in request.environ:
+        raise HTTPFound(location=request.route_url("home"))
+
     request.wutta_config = config
 
     def get_referrer(default=None):

tests/test_handler.py

@@ -38,14 +38,6 @@ class TestWebHandler(WebTestCase):
             url = handler.get_fanstatic_url(self.request, static.logo)
             self.assertEqual(url, "/testing/fanstatic/wuttaweb_img/logo.png")
 
-        # error if environ missing config/data
-        environ = dict(self.request.environ)
-        del environ["fanstatic.needed"]
-        with patch.object(self.request, "environ", new=environ):
-            self.assertRaises(
-                KeyError, handler.get_fanstatic_url, self.request, static.logo
-            )
-
     def test_get_favicon_url(self):
         handler = self.make_handler()
 
@@ -53,12 +45,6 @@ class TestWebHandler(WebTestCase):
         url = handler.get_favicon_url(self.request)
         self.assertEqual(url, "/fanstatic/wuttaweb_img/favicon.ico")
 
-        # returns empty if environ missing config/data
-        environ = dict(self.request.environ)
-        del environ["fanstatic.needed"]
-        with patch.object(self.request, "environ", new=environ):
-            self.assertEqual(handler.get_favicon_url(self.request), "")
-
         # config override
         self.config.setdefault("wuttaweb.favicon_url", "/testing/other.ico")
         url = handler.get_favicon_url(self.request)

tests/test_subscribers.py

@@ -7,6 +7,7 @@ from unittest.mock import MagicMock, patch
 from wuttjamaican.conf import WuttaConfig
 
 from pyramid import testing
+from pyramid.httpexceptions import HTTPFound
 from pyramid.security import remember
 
 from wuttaweb import subscribers
@@ -14,6 +15,10 @@ from wuttaweb import helpers
 from wuttaweb.auth import WuttaSecurityPolicy
 
 
+# TODO: change import above
+mod = subscribers
+
+
 class TestNewRequest(TestCase):
 
     def setUp(self):
@@ -34,6 +39,14 @@ class TestNewRequest(TestCase):
         # request.registry.settings = {'wutta_config': self.config}
         return request
 
+    def test_missing_fanstatic_needed(self):
+        self.pyramid_config.add_route("home", "/")
+        event = MagicMock(request=self.request)
+
+        # should redirect if 'fanstatic.needed' missing from environ
+        with patch.object(self.request, "environ", new={"foo": "bar"}):
+            self.assertRaises(HTTPFound, mod.new_request, event)
+
     def test_wutta_config(self):
         event = MagicMock(request=self.request)